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In a nighttime aspen grove past mile 65 of the Wasatch Front 100-Mile Endurance Run, I feel more like 65 than my real age of 46.

I slow to a stumbling walk on the rocky singletrack and mumble, “Sorry,” to my pacer, Jennifer O’Connor. I want to explain my time-warp theory that I will age to 70 by the time we reach mile 70, but forming words takes too much effort.

Jennifer has known me long enough to read my mood. For distraction, she lobs a question: “Remember when we did the Bay to Breakers together?”

Of course, I answer telepathically. Who forgets her first race?

The week after my 25th birthday, I donned a grass skirt and plastic lei to line up with her in a throng of thousands for that nutty 12K in San Francisco. I had been running only 10 weeks and still had chipmunk cheeks and inner thighs that rubbed together, swish-swish. I still had that dial-up modem and the leaky Corolla. The novelty of sprinting toward the finish in Golden Gate Park left me elated.

She and her husband had gotten into running first, and, when they held parties in their apartment in the Haight, I would lock myself in the bathroom and flip through the running magazines stacked by the toilet. After I watched them finish their first marathon, I started running the next day: Monday, March 7, 1994. Three miles on Berkeley streets, double the farthest I had ever run.

Pretty soon, Jennifer convinced me to try PowerBars, handing one to me like a drug, and we laughed hilariously about the side effects. “Power turds!”

That was before all our relay teams, marathons and 50Ks; before dot-coms and 9/11 and iPhones. Before our parallel career moves, house purchases, health scares and marriage crises. Before we each had two babies who grew into teens.

Suddenly I announce, “I gotta go again,” and branches claw at my legs as I venture into the bushes. Another runner goes by, and I wonder, Why can’t I run like him? Because I feel lame, drained and ancient.

No, I coach myself, I’m just going through a rough patch, and it’ll pass. Then I resume doggedly hiking beside Jennifer.

She and I once went through a rough patch in our friendship and didn’t talk much for a couple of years. As if following my thoughts, retracing old steps, she refers to the time when she left her husband, whom I’ve known even longer. It had felt easier for Jennifer and me to avoid each other than to face the awkwardness of our diverging paths. Eventually, however, we traded messages about our kids, and the correspondence led to running dates again.

Now, like friends who talk in the dark during a sleepover, she tells me, “You’re one of the only ones who stayed close to us both,” meaning her and her ex after the split. “Thank you.”

My throat tightens and eyes blink from emotion as past and present collide. Heavy breathing from the hard climb keeps me from forming coherent sentences, but I want to tell her that I should be thanking her for staying by my side.

Trying to sum up what keeps us together, I blurt: “It’s because you’re an ultrarunner.”

I mean that we’re bonded by more than shared history. It’s the glue of a nerdy obsession with the minutiae of the sport. It’s our insatiable need to run far, mostly for fun and to do our best thinking; sometimes, to escape reality and find the fortitude to face it.

She understands my desire to test my limits with the extreme challenge this mountain range presents, and she drove 1,000 miles just to slog these 25 miles with me. She’s the pacer, but my need for support and camaraderie is mutual.

Someday, perhaps when we run a 5K together with grandkids, I’ll ask her, “Remember when we did Wasatch together?”

Sarah Lavender Smith is a contributing editor at Trail Runner. This article originally appeared in our January 2015 issue.

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